4.3
MEDIUM CVSS 3.1
CVE-2026-53900
Cookie injection was possible when opening a PDF link
Description

Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in TemporaryDocument, allowing a malicious site to inject arbitrary cookies into requests to an unrelated target domain. This vulnerability was fixed in Firefox for iOS 152.0.

INFO

Published Date :

June 16, 2026, 1:16 p.m.

Last Modified :

June 16, 2026, 3:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-53900 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Update Firefox for iOS to version 152.0 or later to fix cookie handling across redirects.
  • Update Firefox for iOS to version 152.0.
  • Ensure the browser is updated regularly.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-53900.

URL Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2043204
https://www.mozilla.org/security/advisories/mfsa2026-56/
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53900 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-53900 weaknesses.

CAPEC-111: JSON Hijacking (aka JavaScript Hijacking) JSON Hijacking (aka JavaScript Hijacking) CAPEC-141: Cache Poisoning Cache Poisoning CAPEC-142: DNS Cache Poisoning DNS Cache Poisoning CAPEC-148: Content Spoofing Content Spoofing CAPEC-218: Spoofing of UDDI/ebXML Messages Spoofing of UDDI/ebXML Messages CAPEC-384: Application API Message Manipulation via Man-in-the-Middle Application API Message Manipulation via Man-in-the-Middle CAPEC-385: Transaction or Event Tampering via Application API Manipulation Transaction or Event Tampering via Application API Manipulation CAPEC-386: Application API Navigation Remapping Application API Navigation Remapping CAPEC-387: Navigation Remapping To Propagate Malicious Content Navigation Remapping To Propagate Malicious Content CAPEC-388: Application API Button Hijacking Application API Button Hijacking CAPEC-665: Exploitation of Thunderbolt Protection Flaws Exploitation of Thunderbolt Protection Flaws CAPEC-701: Browser in the Middle (BiTM) Browser in the Middle (BiTM) CAPEC-21: Exploitation of Trusted Identifiers Exploitation of Trusted Identifiers CAPEC-31: Accessing/Intercepting/Modifying HTTP Cookies Accessing/Intercepting/Modifying HTTP Cookies CAPEC-39: Manipulating Opaque Client-based Data Tokens Manipulating Opaque Client-based Data Tokens CAPEC-59: Session Credential Falsification through Prediction Session Credential Falsification through Prediction CAPEC-60: Reusing Session IDs (aka Session Replay) Reusing Session IDs (aka Session Replay) CAPEC-61: Session Fixation Session Fixation CAPEC-196: Session Credential Falsification through Forging Session Credential Falsification through Forging

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-53900 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-53900 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 16, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
    Added CWE CWE-345
    Added CWE CWE-384
  • New CVE Received by [email protected]

    Jun. 16, 2026

    Action Type Old Value New Value
    Added Description Firefox for iOS preserved cookies set on the initial PDF request across cross-origin HTTP redirects in TemporaryDocument, allowing a malicious site to inject arbitrary cookies into requests to an unrelated target domain. This vulnerability was fixed in Firefox for iOS 152.0.
    Added Reference https://bugzilla.mozilla.org/show_bug.cgi?id=2043204
    Added Reference https://www.mozilla.org/security/advisories/mfsa2026-56/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.